Abstract

We report the use of ultrashort pulses of single electrons for the direct observation of atomic and electronic motion in condensed matter and molecular crystals. Four-dimensional access to space and time on an atomic scale is made possible by the electrons’ picometer-scale de Broglie wavelength, which allows for instructive diffraction into many dynamical Bragg orders¹. The use of single-electron packets² avoids space-charge broadening and photoelectric electron emission with specially synthesized optical pulses at photon energies close to the work function results in electron pulses of less than 100-femtosecond duration. Diffraction from polycrystalline diamond films reveals the favorable influences of matched photon energies on the coherence volume of single-electron wavepackets, which is shown to range above 2 nm without condenser optics or filtering.

© 2011 Optical Society of America